Three faults, one report. The slow poll asks ^TP — the KPA1500's ATU, which
a KPA500 (no ATU) never answers — and ask() dropped the whole connection on
any read timeout: a two-second stall and a reconnect every slow cycle, which
is why buttons lagged and the status read wrong. Worse, every serial reopen
toggled DTR/RTS — and those lines are the KPA500's POWER SWITCH (that is how
the Elecraft utility turns it on), so the amplifier obediently switched off
twenty seconds after its operator pressed nothing but Standby.
Silence is no longer a dead link (write errors still are), ^TP is never asked
again after one silence, the control lines are asserted once and held, and
the baud field becomes a list of the rates these amplifiers actually speak.
rouggy
7e6c0b4f7e